FRE-600: Fix code review blockers

- Consolidated duplicate UndoManagers to single instance
- Fixed connection promise to only resolve on 'connected' status
- Fixed WebSocketProvider import (WebsocketProvider)
- Added proper doc.destroy() cleanup
- Renamed isPresenceInitialized property to avoid conflict

Co-Authored-By: Paperclip <noreply@paperclip.ing>

node_modules/core-js/modules/web.url.to-json.js

@@ -0,0 +1,11 @@
+'use strict';
+var $ = require('../internals/export');
+var call = require('../internals/function-call');
+
+// `URL.prototype.toJSON` method
+// https://url.spec.whatwg.org/#dom-url-tojson
+$({ target: 'URL', proto: true, enumerable: true }, {
+  toJSON: function toJSON() {
+    return call(URL.prototype.toString, this);
+  }
+});